Cryoneurolysis Reduces Postoperative Opioid Use in Patients Undergoing Total Knee Arthroplasty.

BACKGROUND

Cryoanalgesia is increasingly used in total knee arthroplasty (TKA) as a nonopioid pain control modality. This study evaluated the effect of cryoanalgesia on postoperative opioid use and recovery of range of motion in patients who underwent TKA for end-stage knee osteoarthritis.

METHODS

This retrospective case-controlled study included patients who received cryoanalgesia prior to primary, unilateral TKA by one of two fellowship-trained arthroplasty surgeons at a single institution. Exclusion criteria included unicompartmental knee arthroplasty, bilateral TKA, revision knee arthroplasty, revision or reoperation after index arthroplasty, and history of preoperative opioid use. The cryoanalgesia group received ultrasound-guided cryoneurolysis of the anterior femoral cutaneous nerve (FCN), intermediate FCN, medial FCN, and infrapatellar branch of the saphenous nerve prior to TKA. A total of 60 cryoanalgesia cases were matched with 60 controls using age ± five years, sex, and body mass index ± 1.5. The mean age was 69 years (range, 49.5 to 88.1), and the mean body mass index was 32.2 (range, 22.9 to 44.3). There were 84 patients (70%) who were women. Independent sample t-tests were used to compare cumulative postoperative opioid morphine milligram equivalents (MMEs) and recovery of knee flexion between groups.

RESULTS

Patients who received cryoanalgesia required significantly fewer postoperative opioid prescription MMEs than matched controls (362.2 ± 267.2 versus 497.3 ± 336.6, P = 0.016). There was no significant difference in mean knee flexion between the cryoanalgesia and control groups at 2 weeks (94.9 ± 8.5 versus 94.1 ± 7.7°, P = 0.59), 6 weeks (115.1 ± 8.5 versus 113.9 ± 9.2°, P = 0.47), or 3 months (120.5 ± 4.8 versus 119.2 ± 5.8°, P = 0.23) postoperatively. There were no complications that occurred.

CONCLUSIONS

Patients who received cryoanalgesia prior to primary unilateral TKA received significantly fewer postoperative opioid MMEs with no significant difference in knee flexion than matched controls.